Multi-beam light

ABSTRACT

An LED light system for an aircraft may comprise a first LED lamp having a first LED array. The first LED array may include at least a first LED and a second LED. A first optical element may be configured to direct light emitted from the first LED in a first beam centered around a first angle and to direct light emitted from the second LED in a second beam centered around a second angle. The LED light system may further comprise a second LED lamp having a second LED array. The second LED array may include at least a third LED and a fourth LED. A second optical element may be configured to direct light emitted from the third LED in a third beam centered around the first angle and to direct light emitted from the fourth LED in a fourth beam centered around the second angle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of, claims priority to and the benefitof, U.S. Ser. No. 15/356,345 filed Nov. 18, 2016 and entitled“MULTI-BEAM LIGHT,” which is hereby incorporated by reference in itsentirety for all purposes.

FIELD

The present disclosure relates to light systems and, more specifically,to aircraft external light systems.

BACKGROUND

External aircraft light systems may include various lights used duringtaxiing, takeoff, approach and landing for the purpose of illuminatingan area around the aircraft for visibility for the pilot and aircraftconspicuity. The external light systems may include taxi lights, runwayturnoff lights, takeoff lights, landing lights, anti-collision lights,navigation lights, ice detection lights, emergency lights, cargo lights,logo lights and/or novelty lights, among other lights. Taxi lights andrunway turnoff lights may be used for aircraft travel while on theground, for example, when taxiing to and from a gate and a runway.Takeoff lights may be used as the aircraft accelerates and takes off,while landing lights may be used during approach and touchdown.

Commercial aircraft typically employ dedicated landing lights, takeofflights, taxi lights and runway turnoff lights, which may each use one ormore incandescent or halogen lamps. Halogen and incandescent lightingmay have a short operational life and are relatively inefficient interms of lumen output per unit of power consumed. The mounting space onan aircraft occupied by these headlights and the associated wiring islimited such that changing the size, shape or placement of the lamps maybe cost prohibitive. Incandescent lamps used for aircraft headlights maynot be readily replaceable with light emitting diode (LED) lamps, whichhave relatively lower light output compared to an incandescent lamp of asimilar physical size. Further, increasing the light output of an LEDlight system by adding more lamps to an aircraft would add undesirableweight to the aircraft.

SUMMARY

A light emitting diode (LED) light system for an aircraft is disclosedherein, in accordance with various embodiments. The LED light system forthe aircraft may comprise a first LED lamp having a first LED array. Thefirst LED array may include at least a first LED and a second LED. Afirst optical element may be configured to direct light emitted from thefirst LED in a first beam centered around a first angle and to directlight emitted from the second LED in a second beam centered around asecond angle. The LED light system may further comprise a second LEDlamp having a second LED array. The second LED array may include atleast a third LED and a fourth LED. A second optical element may beconfigured to direct light emitted from the third LED in a third beamcentered around the first angle and to direct light emitted from thefourth LED in a fourth beam centered around the second angle.

In various embodiments, the first optical element may comprise at leastone of a reflector or a lens. The first LED array includes a fifth LED,the first optical element may be configured to direct light emitted fromthe fifth LED in a fifth beam centered around a third angle. A distancebetween the first LED and the second LED may be less than 6 millimeters.The first LED lamp may comprise a parabolic aluminized reflector (PAR)lamp having a diameter between 17.8 centimeters and 22.9 centimeters.The first beam of the first LED lamp and the third beam of the secondLED lamp may operate as takeoff lights for the aircraft. The second beamof the first LED lamp and the fourth beam of the second LED lamp mayoperate as landing lights for the aircraft. The first angle may be lessthan 1 degree below a horizontal plane of the aircraft. The second anglemay be 6 degrees below the horizontal plane of the aircraft.

An LED light system retrofitted for an aircraft having a predeterminedmounting area is also provided. The LED light system may comprise afirst beam having a first angle output by a first LED lamp and a secondLED lamp. A second beam having a second angle may be output by the firstLED lamp and the second LED lamp. The first LED lamp may have a diameterbased on the predetermined mounting area. The second LED lamp may have adiameter based on the predetermined mounting area.

In various embodiments, the single optical element may comprise at leastone of a reflector or a lens. The LED array may include a first LED anda second LED disposed in a fixed position relative to the at least oneof the reflector or the lens. The LED lamp may have a diameter based onthe preexisting mounting area. The LED lamp may comprise a parabolicaluminized reflector (PAR) lamp having the diameter between 17.8centimeters and 22.9 centimeters. The LED lamp may operate as a takeofflight for the aircraft and as a landing light for the aircraft.

A method of replacing a light system of an aircraft with an LED lightsystem retrofitted for the aircraft is also provided. The method maycomprise the steps of defining a defined lamp diameter based on apreexisting mounting area of the light system, and installing a firstLED lamp having the defined lamp diameter in the preexisting mountingarea. The first LED lamp may have multiple LEDs that define an LEDarray. The LED array may be configured such that beams centered arounddifferent angles are formed by light emitted from different LEDs in theLED array being directed by a single optical element.

In various embodiments, the first LED array may include at least a firstLED and a second LED. The method may further comprise positioning thefirst LED relative to the first single optical element to direct lightemitted from the first LED in a first beam centered around a firstangle, and positioning the second LED relative to the first singleoptical element to direct light emitted from the second LED in a secondbeam centered around a second angle. The first beam angle may beconfigured for a takeoff light for the aircraft, and wherein the secondbeam angle may be configured for a landing light of the aircraft. Thefirst LED array may include a third LED positioned relative to the firstsingle optical element to direct light emitted from the third LED in athird beam centered around a third angle. The first LED lamp maycomprise a PAR lamp. The defined lamp diameter may be between 17.8centimeters and 22.9 centimeters. The method may further compriseinstalling a second LED lamp having the defined lamp diameter in thepreexisting mounting area, the second LED lamp having multiple LEDs thatdefine a second LED array. The second LED array may be configured suchthat beams centered around different angles are formed by light emittedfrom different LEDs in the second LED array being directed by a secondsingle optical element.

The foregoing features and elements may be combined in variouscombinations without exclusivity, unless expressly indicated otherwise.These features and elements as well as the operation thereof will becomemore apparent in light of the following description and the accompanyingdrawings. It should be understood, however, the following descriptionand drawings are intended to be exemplary in nature and non-limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

The subject matter of the present disclosure is particularly pointed outand distinctly claimed in the concluding portion of the specification. Amore complete understanding of the present disclosure, however, may bestbe obtained by referring to the detailed description and claims whenconsidered in connection with the figures, wherein like numerals denotelike elements.

FIG. 1 illustrates an exemplary aircraft, in accordance with variousembodiments;

FIGS. 2A, 2B and 2C illustrate an aircraft during various stages ofoperation, in accordance with various embodiments;

FIG. 3 illustrates an LED lamp for an aircraft light system, inaccordance with various embodiments;

FIGS. 4A and 4B illustrate an LED arrangement for an aircraft lightsystem, in accordance with various embodiments; and

FIGS. 5A, 5B and 5C illustrate a methods of retrofitting a light systemof an aircraft an aircraft, in accordance with various embodiments.

DETAILED DESCRIPTION

All ranges and ratio limits disclosed herein may be combined. It is tobe understood that unless specifically stated otherwise, references to“a,” “an,” and/or “the” may include one or more than one and thatreference to an item in the singular may also include the item in theplural.

The detailed description of various embodiments herein makes referenceto the accompanying drawings, which show various embodiments by way ofillustration. While these various embodiments are described insufficient detail to enable those skilled in the art to practice thedisclosure, it should be understood that other embodiments may berealized and that logical, chemical, optical and mechanical changes maybe made without departing from the spirit and scope of the disclosure.Thus, the detailed description herein is presented for purposes ofillustration only and not of limitation. For example, the steps recitedin any of the method or process descriptions may be executed in anyorder and are not necessarily limited to the order presented.Furthermore, any reference to singular includes plural embodiments, andany reference to more than one component or step may include a singularembodiment or step. Also, any reference to attached, fixed, connected,or the like may include permanent, removable, temporary, partial, full,and/or any other possible attachment option. Additionally, any referenceto without contact (or similar phrases) may also include reduced contactor minimal contact. Cross hatching lines may be used throughout thefigures to denote different parts but not necessarily to denote the sameor different materials.

As used herein, “aft” refers to the direction associated with the tail(e.g., the back end) of an aircraft, or generally, to the direction ofexhaust of the gas turbine. As used herein, “forward” refers to thedirection associated with the nose (e.g., the front end) of an aircraft,or generally, to the direction of flight or motion.

The present disclosure relates to light emitting diode (LED) based lightsystems for external aircraft lighting and to retrofitting existingexternal aircraft light assemblies with LED assemblies withoutsignificant redesign of the mounting space, wiring or control systemsfor the lighting. Incandescent or halogen parabolic aluminized reflector(PAR) lamps used for conventional aircraft headlights may be mounted tothe wings and/or landing gear of the aircraft. Referring to landinglights and takeoff lights as an example, an aircraft may employ a totalof four incandescent PAR lamps for this purpose. Two of the incandescentPAR lamps may operate as landing lights, and the other two of theincandescent PAR lamps may operate as takeoff lights. The presentdisclosure relates to systems and methods for replacing incandescent PARlamps with LED systems within the same space on the aircraft previouslyoccupied by incandescent PAR lamps, while still providing with the LEDsystems sufficient light output (luminous flux) and light intensity(luminous intensity).

While LEDs are more efficient in terms of output per unit power (lumensper watt), LEDs produce heat that limits the efficiency of the LEDunless the heat is removed from the system. Thermal management systemsfor LEDs, such as heat sinks, may conduct heat away from the LEDs tocontrol the operating temperature of LED lamps. The space used tomaintain safe and efficient operating temperatures for an LED lamplimits the density of LEDs that can be used in a given space.

Incandescent PAR lamps may include a bulb and a reflector encased in ahousing and may be configured in industry standard sizes or diameters.For example, a commercial aircraft may employ a quantity of four 500watt (or greater) incandescent PAR64 lamps, i.e., two incandescent PAR64lamps as landing lights and two incandescent PAR64 lamps as takeofflights. The numeral “64” in “PAR64” refers to a diameter of the lampmeasured in ⅛ inch increments, e.g, a PAR64 may have a diameter of 64times ⅛ inch, or approximately 8 inches (20.3 centimeters (cm)). An LEDPAR lamp having the same or similar diameter as an incandescent PAR lampmay produce a lower light output. A single incandescent PAR64 lamp mayproduce between 15,000 lumens and 20,000 lumens. An LED PAR64 lamp mayproduce less than 10,000 lumens. Thus, simply replacing an incandescentPAR64 with an LED PAR64 may not produce sufficient light output to meetSAE ARP 693 recommendations (SAE Aircraft Recommended Practice 693includes recommended standards for headlights on an aircraft) and beacceptable to most pilots. The LED light systems disclosed hereinprovide, in various embodiments, a solution for retrofitting an aircraftpreviously configured for incandescent PAR lamps. The disclosed LEDsystems, in various embodiments, provide LED lamp assemblies that fitwithin existing mounting space on the aircraft and provide sufficientlight output, which is comparable to the incandescent lamps beingreplaced.

With reference to FIG. 1, an aircraft 10 on runway 12 is shown in afront view, in accordance with various embodiments. Aircraft 10 maycomprise a fuselage 14, which may be coupled to and/or comprise a pairof wings 16. Aircraft 10 may comprise a nose landing gear 18 locatedunder the nose 20 of aircraft, and may further comprise a right and leftlanding gear 22. A light system 24 of aircraft 10 may comprise aplurality of LED lamps 30, which may comprise exterior or externalaircraft lights that illuminate areas around the aircraft 10 while theaircraft 10 is on the ground or in flight. Light system 24 may includeLED lamps 30 a, 30 b, 30 c, 30 d, which may collectively be referred toas LED lamps 30. In various embodiments, LED lamp 30 a and LED lamp 30 bmay both be mounted to nose landing gear 18. LED lamp 30 c and LED lamp30 d may each be mounted to a wing 16, such as on the wing roots or onthe front edges of the wings 16. LED lamps 30 may operate as a takeofflights, landing lights, taxi lights and/or a runway turnoff light. Asillustrated in FIG. 1, for example, LED lamps 30 are multi-beam lightassemblies configured to operate as takeoff lights and landing lights.

Referring to FIGS. 2A, 2B and 2C, an aircraft during various stages ofoperation is shown, in accordance with various embodiments. Thedirection that nose 20 of aircraft 10 is pointing may be referred to asa heading or pointing direction. Nose 20 of aircraft 10 may be pointedalong a central longitudinal axis A-A′ of aircraft 10, for example, in adirection forward of fuselage 14. Central longitudinal axis A-A′ isoriented along the z axis on the provided xyz axes, which may defined berelative to aircraft 10, wherein aircraft 10 points in the positive zdirection. The terms “horizontal” and “vertical” may be relative to thehorizontal plane of aircraft 10, i.e., the xz plane, rather thanrelative to the ground. A measurement point displaced in the positive ydirection from a given reference point may be considered “above” or on“top” of the given reference point. A measurement point displaced in thenegative y direction from the given reference point may be considered“below” or on “bottom” of the given reference point. In that regard, theterms “top” and “bottom” may refer to relative positions along the yaxis.

LED lamps 30 may be configured to operate in a plurality of operatingmodes. Three operating modes of aircraft 10 are illustrated by FIGS. 2A,2B and 2C including takeoff, touch down, and a landing approach. FIG. 2Aillustrates the aircraft in ground roll where the aircraft 10accelerates prior to takeoff. LED lamp 30 d may be configured to providea first beam 40. LED lamp 30 d may be configured to provide a first beam42. First beams 40, 42 may be useful when aircraft 10 is taking offand/or landing. First beams 40, 42 may be aimed generally forward ofnose 20 with a vertical beam distribution centered at a beam center. Abeam center of first beam 40 of LED lamp 30 d is shown as the line offirst beam 40, and a beam center of first beam 42 of LED lamp 30 b isshown as the line of first beam 42.

In various embodiments, first beams 40, 42 may be aimed about −0.5degrees (°) relative to the central longitudinal axis A-A′ of theaircraft 10, wherein “about” in this context only means+/−1°. Stateddifferently, a beam center of each of the first beams 40, 42 may be atfirst angle α (“alpha”) of 0.5° below the aircraft horizontal z axis.Similarly, LED lamp 30 a and LED lamp 30 c (from FIG. 1) mounted to theright side of aircraft 10 may each also output a first beam centered atthe first angle α of about −0.5°, wherein “about” in this context onlymeans+/−1°. First beams 40, 42 also have a horizontal beam distributionin the xz plane, with the horizontal beam distribution centered at thebeam center. In various embodiments, a horizontal beam distributionangle of first beams 40, 42 may be about 3° centered along the centrallongitudinal axis A-A′, or otherwise centered along an aiming direction,wherein “about” in this context only means+/−1°.

FIG. 2B illustrates the aircraft in approach where the aircraft 10touches the ground upon landing. LED lamp 30 d may be configured toprovide a second beam 50. LED lamp 30 d may be configured to provide asecond beam 52. Second beams 50, 52 may be useful while aircraft 10 istouching down on the ground upon landing. Second beams 50, 52 may beaimed generally forward of nose 20 with a vertical beam distributioncentered at a beam center. A beam center of second beam 50 of LED lamp30 d is shown as the line of second beam 50, and a beam center of secondbeam 52 of LED lamp 30 b is shown as the line of second beam 52.

In various embodiments, second beams 50, 52 may be aimed about −6°relative to the central longitudinal axis A-A′ of the aircraft 10,wherein “about” in this context only means+/−2°. A beam center of eachof the second beams 50, 52 may be at second angle β (“beta”) of 6° belowthe aircraft horizontal z axis. Similarly, LED lamp 30 a and LED lamp 30c (from FIG. 1) mounted to the right side of aircraft 10 may each alsooutput a second beam centered at the second angle β of about −6°,wherein “about” in this context only means+/−2°. Second beams 50, 52also have a horizontal beam distribution in the xz plane, with thehorizontal beam distribution centered at the beam center.

FIG. 2C illustrates the aircraft in approach where the aircraft 10descends prior to landing on the ground. LED lamps 30 d may beconfigured to provide a third beam 60. LED lamps 30 d may be configuredto provide a third beam 60. Third beams 60, 62 may be useful whileaircraft 10 is approaching the ground for landing. Third beams 60, 62may be aimed generally forward of nose 20 with a vertical beamdistribution with a vertical beam distribution centered at a beamcenter. A beam center of third beam 60 of LED lamp 30 d is shown as theline of third beam 60, and a beam center of third beam 62 of LED lamp 30b is shown as the line of third beam 62.

In various embodiments, third beams 60, 62 may be aimed about −12°relative to the central longitudinal axis A-A′ of the aircraft 10,wherein “about” in this context only means+/−3°. A beam center of eachof the third beams 60, 62 may be at a third angle δ (“delta”) of 12°below the aircraft horizontal z axis. Similarly, LED lamp 30 a and LEDlamp 30 c (from FIG. 1) mounted to the right side of aircraft 10 mayeach also output a third beam centered at the third angle δ of about−12°, wherein “about” in this context only means+/−3°. Third beams 60,62 also have a horizontal beam distribution in the xz plane, with thehorizontal beam distribution centered at the beam center.

Thus, LED lamps 30 a, 30 b, 30 c, 30 d may each be multi-beam lampsconfigured to output a first beam, such as first beam 40 aimed at −0.5°.A combined light output of the first beams of LED lamps 30 a, 30 b, 30c, 30 d may produce at least as much luminous flux as two incandescentlamps of comparable diameter. In that regard, LED lamps 30 a, 30 b, 30c, 30 d may operate as takeoff lights. Further, LED lamps 30 a, 30 b, 30c, 30 d may each be configured to output a second beam, such as secondbeam 50 aimed at −6°, and each may further be configured to output athird beam, such as third beam 60 aimed at −12°. Again, a combined lightoutput of the second beams or the third beams of LED lamps 30 a, 30 b,30 c, 30 d may produce at least as much luminous flux as twoincandescent lamps of comparable diameter. In that regard, LED lamps 30a, 30 b, 30 c, 30 d may also operate as landing lights. Where aconventional aircraft employed two incandescent lamps as landing lightsand two incandescent lamps as takeoff lights, the present disclosureprovides a light system 24 having four LED lamps with all four LED lampsoperating as both landing lights and takeoff lights. Accordingly, thelight system 24 (FIG. 1) operates as an LED light system to replaceincandescent landing lights and takeoff lights by providingmulti-directional LED lamps.

Although discussed and illustrated as a four lamp example using PAR64lamps for takeoff and landing lights, it will be understood that thepresent disclosure is applicable to other quantities of lamps mounted toan aircraft and to additional sizes of lamps as well as other aircraftlighting systems, such as taxi lights, runway turnoff lights and otherlights. By example, two incandescent lamps each having different beamangles may be replaced with two multi-beam LED, wherein each multi-beamLED lamp outputs at least two beam angles.

Referring to FIG. 3, an arrangement for an LED lamp for an aircraftlight system is shown, in accordance with various embodiments. Invarious embodiments, each of LED lamps 30 a, 30 b, 30 c, 30 d, asdiscussed with respect to FIGS. 1, 2A, 2B and 2C, may be configuredsimilarly to the LED lamp 30 shown in FIG. 3. Each LED lamp 30 of lightsystem 24 may include one or more optical elements 70, which may bereflectors 72 and/or lenses. The optical elements 70 of LED lamp 30 areillustrated in FIG. 3 as reflectors 72. A reflector 72 may besubstantially parabolic. LED lamp 30 is illustrated in FIG. 3 as an LEDPAR64 having a quantity of fourteen of reflectors 72 arranged in a twodimensional array within a housing 74 of LED lamp 30. LED lamp 30 mayhave various quantities of reflectors 72. A quantity of reflectors 72used in LED lamp 64 may be determined at least in part by the size ofhousing 74. In retrofitting LED lamp 30 to an aircraft configured with apredetermined mounting area, a size and/or diameter D of LED lamp 30 maybe configured to be accommodated within the predetermined mountingspace, or to fit within the predetermined mounting area. In variousembodiments, LED lamp 30 and/or housing 74 may have a diameter D between3 inches (7.6 cm) and 12 inches (30.5 cm), or between 5 inches (12.7 cm)and 12 inches (30.5 cm), or between 6 inches (15.2 cm) and 10 inches(25.4 cm), or more specifically between 7 inches (17.8 cm) and 9 inches(22.9 cm), and nominally 8 inches (20.3 cm).

LED lamp 30 may further include a plurality of light sources 76 arrangedwith an optical element 70 positioned to aim one or more light beamsfrom light sources 76. Light sources 76 may be groups of LEDs or anarray of LEDs (see FIGS. 4A and 4B). An optical element 70 may beassociated with a light source 76 to form a portion of the LED lamp 30.A plurality of optical elements, such as reflectors 72, may bepositioned with one or more light sources 76, to provide the multi-beamlight output of LED lamp 30.

Referring to FIGS. 4A and 4B, an optical element and LED arrangement foran aircraft light system is shown, in accordance with variousembodiments. An optical element 70 for an LED lamp 30 (from FIG. 3) isillustrated as a reflector 72 in FIG. 4A. Light source 76 (from FIG. 3)is illustrated as an LED array 80 comprising a plurality of individualLEDs. An LED array 80 may include a first LED 82, a second LED 84 and athird LED 86. LED array 80 may be a linear array, a two dimensionalarray or other suitable arrangement. The optical element 70 for an LEDlamp 30 (from FIG. 3) is illustrated as a lens 78 in FIG. 4B. The lens78 is illustrated simply as a line, however, lens 78 may have at leastone curved surface, and either or both surfaces of lens 78 may be convexor concave.

Each LED lamp 30 may include one or more LED arrays 80. The LED arrays80 may each include a first LED 82 and second LED 84. An optical element70 may be configured to direct light emitted from first LED 82 in afirst beam 40 centered around a first angle α and to direct lightemitted from the second LED 84 in a second beam 50 centered around asecond angle β. Each LED array 80 may further include a third LED 86.Optical element 70 may be configured to direct light emitted from thirdLED 86 in a third beam 60 centered around a third angle δ. Opticalelement 70 may comprise at least one of a reflector 72 or a lens 78. Theoptical element for LED array 80 will be discussed in terms of reflector72, but also applies to lens 78.

Each LED 82, 84, 86 of LED array 80 may have a fixed position withrespect to reflector 72. The individual LEDs may be separated by adistance between adjacent LEDs, and each LED 82, 84, 86 may bepositioned at selected distance from a focal point of reflector 72,wherein the focal point of reflector 72 is illustrated at a point alonga reflector axis P at the focal length F from a surface of reflector 72.For example, first LED 82 may be placed within 1 millimeter (mm) of thefocal point of reflector 72. Second LED 84 may be separated from firstLED 82 a distance S1, and similarly, may be offset from reflector axis Pby a distance S1. A distance S1 between first LED 82 and second LED 84may be less than 6 mm, or less than 5 mm, or less than 4 mm, or lessthan 3 mm, or less than 2 mm. Third LED 86 may be separated from secondLED 84 by a distance S2. A distance S2 between second LED 84 and thirdLED 86 may be less than 6 mm, or less than 5 mm, or less than 4 mm, orless than 3 mm, or less than 2 mm. The distances S1, S2 of separationbetween first LED 82 and second LED 84, and second LED 84 and third LED86, respectively, may be selected based on the focal length F anddiameter of reflector 72 and further based on the number of reflectors72 in LED lamp 30 (from FIG. 3) and the light output of each LED 82, 84,86. A reflector 72 may be modified to fit into an array or lamp, forexample, by truncating the reflector 72. The diameter of reflector 72may refer to the baseline diameter of a reflector 72 prior to truncatingthe reflector 72 and fitting the reflector into LED lamp 30. Thus, thereflector diameter may indicate the relative shape and/or curvature ofthe reflector 72, regardless of truncation. Thus, a reflector 72 may bea portion of a reflector, and a reflector diameter may be relative sizeand shape of the reflector or a portion of the reflector.

TABLE 1 shows arrangements of LEDs and reflectors that can be placedinto an LED PAR64 lamp to achieve 5,000 lumens of light output atvarious beam angles, in accordance with various embodiments.

TABLE 1 Focal Length (mm) Beam angle (degrees) 10 15 20 30 50 Distance 1 (6)  (4)  (3) (2) (1) between 2 11  (8)  (5) (4) (2) LEDs (mm) 3 17 11 9 6 (3) 4 22 15 11 7 (5) 5 27 18 14 9 6 6 31 22 17 11  7 ReflectorDiameter (mm) 40 60 80 120  200  Quantity of Reflectors 18 14 12 10  4Luminous flux per LED 278  357  417  500  1250   (lumens)

TABLE 1 further shows various sizes and quantities of optical elements,such as reflectors 72 from FIG. 3, and various positions of LEDs withinan LED array, such as LEDs 82, 84, 86 from FIG. 4A, for producingvarious beam angles for a multi-beam LED lamp, such as LED lamp 30.

Referring to FIGS. 2B and 4A and to TABLE 1, a desired beam angle ofaircraft headlights during touchdown may be 6° as shown by second angleβ of second beams 50, 52 in FIG. 2B. Further, a desired light outputduring touchdown may be provided by a combined light output from thesecond beams 50 (see FIG. 4A) of multiple 5,000 lumen LED PAR64 lamps.As discussed above, retrofitting an aircraft previously configured forincandescent PAR64 lamps involves fitting the LED lamps within apre-determined mounting area. Thus, diameter and quantity of reflectorsfor the LED lamp were selected to have a total diameter that is similarto or less than a diameter of an incandescent PAR64 lamp.

As shown in TABLE 1 by example, an LED lamp 30 that may produce 5,000lumens and a beam angle of 6° is configured with four reflectors eachhaving a focal length of 50 mm and a reflector diameter of up to 200 mm,and with four LEDs spaced at a distance of 5 mm from each reflectoraxis, with each LED having a luminous flux output of 1,250 lumens.

As shown in TABLE 1 by further example, an LED lamp 30 that may produce5,000 lumens and a beam angle of 6° is configured with ten reflectorseach having a focal length of 30 mm and a reflector diameter of up to120 mm, and with ten LEDs spaced at a distance of 3 mm from eachreflector axis, with each LED having a luminous flux output of 500lumens.

Relating this example to FIGS. 2B, 3 and 4A, an LED lamp 30 may have tenreflectors 72, in accordance with various embodiments. Each of the tenreflectors 72 may have at least one LED array 80 associated with areflector 72, and thus, LED lamp 30 may have at least ten LED arrays 80.Each of the ten LED array 80 may include at least a second LED 84 spacedat a distance S1 of 3 mm from reflector axis P. Light beams from each ofthe second LEDs 84 are reflected by the associated reflector 72 toproduce a second beam 50. Each of the second LEDs 84 may have an outputof 500 lumens, such that the combined output of ten of the second LEDs84 aimed at a beam angle of 6° provides an output by the LED lamp 30 of5,000 lumens at a beam angle of 6°. LED lamp 30 may further be part of alight system 24 (FIG. 1) that includes a plurality of LED lamps 30 thatalso produce a second beam 50 at a beam angle of 6°. Light system 24including one or more LED lamps 30 retrofitted onto aircraft 10 toprovide a multi-beam LED light system, thereby replacing a non-LEDlanding lights and takeoff lights with LED landing lights and takeofflights.

With reference to FIGS. 5A, 5B and 5C, methods of retrofitting the lightsystem of the aircraft are shown, in accordance with variousembodiments. With reference to FIG. 5A, a method 200 of manufacturing anLED light system retrofitted for an aircraft is shown, in accordancewith various embodiments. An aircraft 10 may have mechanical andelectrical fittings configured for one or more incandescent PAR lamps.The incandescent PAR lamp base and housing may define a size and shapeof the socket and available mounting area on the aircraft 10. Method 200may comprise the steps of defining a lamp diameter based on apredetermined mounting area defined by the aircraft (step 202),selecting a first beam angle and a second beam angle (step 204), anddisposing a first LED array within a first LED lamp having a firstreflector (step 206). The first LED lamp 30 may have the defined lampdiameter. The first LED array, such as LED array 80, may include a firstLED 82 and a second LED 84. The first LED array may include a fifth LED(similar to third LED 86). The first optical element 70 may beconfigured to direct light emitted from the fifth LED in a fifth beam(similar to third beams 60, 62) centered around a third angle.

Method 200 may further comprise the step of disposing a second LED arraywithin a second LED lamp having a second reflector (step 208). Thesecond LED lamp 30 may have the defined lamp diameter. The second LEDarray, such as LED array 80, may include a third LED (similar to firstLED 82) and a fourth LED (similar to second LED 84). Method 200 mayfurther comprise the steps of positioning the first LED array relativeto the first reflector such that the first LED outputs the first beamangle and the second LED outputs the second beam angle (step 210),positioning the second LED array relative to the second reflector suchthat the third LED outputs the first beam angle and the fourth LEDoutputs the second beam angle (step 212), and installing the first LEDlamp and the second LED lamp within the predetermined mounting area(step 214).

With reference to FIG. 5B, a method 300 for replacing a light system ofan aircraft with an LED light system retrofitted for the aircraft isshown, in accordance with various embodiments. Method 300 may comprisethe steps of defining a lamp diameter based on a preexisting mountingarea of the light system (step 302), disposing a first LED array withina first LED lamp having a first optical element (step 304). The firstLED array may include at least a first LED 82 and a second LED 84.Method 300 may further comprise the steps of positioning the first LEDrelative to the first optical element to direct light emitted from thefirst LED in a first beam centered around a first angle (step 306),positioning the second LED relative to the first optical element todirect light emitted from the second LED in a second beam centeredaround a second angle (step 308), and installing a first LED lamp havingthe defined lamp diameter in the preexisting mounting area (step 310).

In various embodiments, the first angle α may be configured for atakeoff light for the aircraft, and the second angle β may be configuredfor a landing light of the aircraft. The first LED array, such as LEDarray 80, may further include a third LED 86 positioned relative to thefirst optical element 70 to direct light emitted from the third LED 86in a third beam centered around a third angle δ.

With reference to FIG. 5C, a method 400 of replacing a light system ofan aircraft with an LED light system retrofitted for the aircraft isshown, in accordance with various embodiments. Method 400 may comprisethe steps of defining a defined lamp diameter based on a preexistingmounting area of the light system (step 402), and installing a first LEDlamp having the defined lamp diameter in the preexisting mounting area(step 404).

Method 400 may further include installing a second LED lamp having thedefined lamp diameter in the preexisting mounting area (step 406). Thesecond LED lamp 30 may have multiple LEDs that define a second LED array80. The second LED array 80 may be configured such that beams centeredaround different angles are formed by light emitted from different LEDsin the second LED array 80 being directed by a second single opticalelement 70. Thus, methods of retrofitting the light system of theaircraft are disclosed.

Benefits and other advantages have been described herein with regard tospecific embodiments. Furthermore, the connecting lines shown in thevarious figures contained herein are intended to represent exemplaryfunctional relationships and/or physical couplings between the variouselements. It should be noted that many alternative or additionalfunctional relationships or physical connections may be present in apractical system. However, the benefits, advantages, and any elementsthat may cause any benefit or advantage to occur or become morepronounced are not to be construed as critical, required, or essentialfeatures or elements of the disclosure. The scope of the disclosure isaccordingly to be limited by nothing other than the appended claims, inwhich reference to an element in the singular is not intended to mean“one and only one” unless explicitly so stated, but rather “one ormore.” Moreover, where a phrase similar to “at least one of A, B, or C”is used in the claims, it is intended that the phrase be interpreted tomean that A alone may be present in an embodiment, B alone may bepresent in an embodiment, C alone may be present in an embodiment, orthat any combination of the elements A, B and C may be present in asingle embodiment; for example, A and B, A and C, B and C, or A and Band C.

Systems, methods and apparatus are provided herein. In the detaileddescription herein, references to “various embodiments”, “oneembodiment”, “an embodiment”, “an example embodiment”, etc., indicatethat the embodiment described may include a particular feature,structure, or characteristic, but every embodiment may not necessarilyinclude the particular feature, structure, or characteristic. Moreover,such phrases are not necessarily referring to the same embodiment.Further, when a particular feature, structure, or characteristic isdescribed in connection with an embodiment, it is submitted that it iswithin the knowledge of one skilled in the art to affect such feature,structure, or characteristic in connection with other embodimentswhether or not explicitly described. After reading the description, itwill be apparent to one skilled in the relevant art(s) how to implementthe disclosure in alternative embodiments.

Furthermore, no element, component, or method step in the presentdisclosure is intended to be dedicated to the public regardless ofwhether the element, component, or method step is explicitly recited inthe claims. No claim element is intended to invoke 35 U.S.C. 112(f)unless the element is expressly recited using the phrase “means for.” Asused herein, the terms “comprises”, “comprising”, or any other variationthereof, are intended to cover a non-exclusive inclusion, such that aprocess, method, article, or apparatus that comprises a list of elementsdoes not include only those elements but may include other elements notexpressly listed or inherent to such process, method, article, orapparatus.

What is claimed is:
 1. A light emitting diode (LED) light system for anaircraft, comprising: a first LED lamp having a first LED array, thefirst LED array including a first LED, a second LED, and a third LED; afirst optical element configured to direct light emitted from the firstLED in a first beam centered around a first angle and to direct lightemitted from the second LED in a second beam centered around a secondangle, wherein the first LED is aligned with an axis of the firstoptical element, the second LED is positioned above the first LED, andthe third LED is positioned above the second LED; a second LED lamphaving a second LED array, the second LED array including a fourth LED,a fifth LED, and a sixth LED; and a second optical element configured todirect light emitted from the fourth LED in a third beam centered aroundthe first angle and to direct light emitted from the fifth LED in afourth beam centered around the second angle.
 2. The LED light system ofclaim 1, wherein the first optical element comprises at least one of areflector or a lens.
 3. The LED light system of claim 1, wherein adistance between the first LED and the second LED is less than 6millimeters.
 4. The LED light system of claim 1, wherein the first LEDlamp comprises a parabolic aluminized reflector (PAR) lamp having adiameter between 17.8 centimeters and 22.9 centimeters.
 5. The LED lightsystem of claim 1, wherein the first beam of the first LED lamp and thethird beam of the second LED lamp operate as takeoff lights for theaircraft, and wherein the second beam of the first LED lamp and thefourth beam of the second LED lamp operate as landing lights for theaircraft.
 6. The LED light system of claim 1, wherein the first angle isless than 1 degree below a horizontal plane of the aircraft, and whereinthe second angle is 6 degrees below the horizontal plane of theaircraft.